package Fecse;

public class Tesetr {

    private int day;
    public void change1(int i){
        i=1234;
    }//传输副本，不存值
    public void chang2(BirthDate b){
        b=new BirthDate(22,3,4004);
    }
    public void change3(BirthDate b){
        b.setDay(22);
    }

}
